The present study investigated the association of important genetic variations in FAS -670A/G and FASL -124A/G in patients with tuberculosis and the influence of these polymorphisms on the plasma levels of sFas and sFasL and the gene expression of FASL, since the anti-apoptotic or pro-apoptotic activity of these molecules can determine the progression of M. tuberculosis infection and the prognosis of tuberculosis [25,26,27,28,29]. The gene discussed is FAS; the disease is tuberculosis.